Some cloud services require many virtual machines (VMs) to efficiently support multiple tenants and/or multiple concurrent jobs. Examples include cloud services that manage very large datasets such as vHadoop from VMware, Inc., virtual desktop services such as Virtual Desktop Infrastructure (VDI) from VMware, Inc., and cloud service providers such as the CLOUD FOUNDRY brand computer services (e.g., MONGODB brand computer software). Each of these services, and others, requires a large pool of VMs to be created and scaled-back over time and on demand, dependent on the workload of the service. Further, the services require VM instantiation and teardown operations to be fast and highly elastic.
However, the existing operations for VM instantiation and teardown are slow and highly processor intensive. For example, it may take 20 seconds to boot one of the VMs using some existing systems. Some existing systems rely on linked clones for VM instantiation. While some linked VM clones use small delta disks that reference a larger base disk of another VM, these systems lack a mechanism for online customization of the instantiated VMs (e.g., performed while the VMs are powered-on). For example, as linked VM clone functionality does not inherently include customization, some of the existing systems rely on offline domain join techniques (e.g., performed while the VMs are powered-off). As another example, these systems are unable to configure instantiated VMs with different states. Further, many guest operating systems require rebooting, or other operations with a high time cost, to set identities within the instantiated VMs due to restrictions at the operating system level.